Device for driving the yarn layer of a textile machine



5. FRENZEL Apiil 29, 1969 DEVICE FOR DRIVING THE YARN LAYER OF A TEXTILE MACHINE Sheet Filed Jan. 16, 1967 INVENTOR JEATRIM fies/vzeL April 1969 B FRENZEL. 3,440,840

DEVICE FOR DRIVING THE YARN LAYER OF A TEXTILE MACHINE Filed Jan. 16, 1967 Sheet 2 of 2 INVENTOR Jaeneww fiFEA/ZEL United States Patent 3,440,840 DEVICE FOR DRIVING THE YARN LAYER OF A TEXTILE MACHINE Bertram Frenzel, Karl-Marx-Stadt, Germany, assignor to VEB Nahwerkmaschinenbau Malimo Karl-Marx-Stadt,

Karl-Marx-Stadt, Germany Filed Jan. 16, 1967, Ser. No. 609,487 Int. Cl. D041) 23/00 US. Cl. 66-84 5 Claims ABSTRACT OF THE DISCLOSURE In a textile producing machine a yarn layer carriage reciprocates over guide rails back and forth across the entire width of the machine. An endless chain is coupled to the carriage and passes over four pairs of spacing rollers disposed pairwise in a vertical path and passing the endless chain over a horizontal path between the pairs of rollers. The carriage is coupled to the chain by a lever arm which is adapted to rock and permit entry of the coupling point thereof into the vertical path between a respective pairs of rollers. The entry of the coupling point into the respective vertical paths defines the rest period for the carriage at both ends of the horizontal path before reversal.

BACKGROUND OF THE INVENTION Field of the invention The present invention relates generally to a device for driving a yarn layer carriage which reciprocates in a machine producing a textile fabric, and, more particularly, to a yarn layer carriage of a warp-knitting machine, in which by means of an endless chain or the like, the yarn layer is driven back and forth.

Description of the prior art It is known to put a carriage and thus the layer of a fiat knitting machine into motion by means of a push crank drive of which the crank radius is changeable. The crank of such driving gear drives a small toothed gear by means of a toothed rack. A larger driving gear for an endless chain is arranged on the shaft of the small toothed gear. The driven gear of this chain is of the same size as its driving gear. A still larger driving gear is provided on the shaft of the first gear to drive a second endless chain to which the carriage, thus the layer is coupled. In the last. mentioned drive, the changeable crank radius of the thrust crank gear effects only a change of the length of the path of movement of the carriage and thus of the layer.

There is also known a driving arrangement for the thread guide of a fiat hosiery knitting machine. This drive is provided with an endless chain with which the follower. pin of the thread guide bars is coupled. The coupling action is achieved by means of a bolt which is fastened onto the endless chain, and by means of a coulisse which is provided on the follower pin, and into which the bolt engages. The endless chain is provided on both sides with guide rollers with the help of which the stringer of the endless chain, same being coupled with the follower pin, can be rerouted in directions which extend vertical to the path of movement of the follower pin. The coulisse is adjusted to these directions, so that the coupling bolt, when entering intothe vertical directions of the endless chains, will be displaced idle or neutral inside the coulisse. The follower pin comes thereby to a stand-still or halt. The afore-inentioned guide rollers can be adjusted pair-by-pair parallel to the path of movement of the follower pin, again for the purpose to change the length of the path of movement of the thread guide.

Drives are also known for knitting machines which are 3,440,840 Patented Apr. 29, 1969 ice provided with a push crank drive having a shaft which is put into alternating rotation, whereby the latter drives an endless chain which is coupled with a yarn layer. However, such driving devices are less suitable for knitting machines with large working width, namely since the endless chain drives the yarn layer in such a way that it is geared only once, so that the push crank drive must 1 have a too large crank radius in order to be able to cover the long path of the yarn layer. This shortcoming cannot be overcome by simply providing a second transmission gear on the drive shaft of the chain which is coupled with the yarn layer in addition to the reduction which is already provided on the drive shaft of the push crank drive, since this will result in an inaccurate positioning of the reversal points of the yarn layer. However, such an inaccurate positioning of the reversal points must be prevented under any circumstances in warp-knitting machines, since the yarn must be introduced into the hooks of the endless transporting chain which feeds the bunch of the yarns, the latter being in zigzag form, to a point in the machine where the loops are formed. It is a prerequisite for this action that the ends of the path of movement of the yarn layer should always fall exactly on the same point. This prerequisite could not be met even with the help of a changeable crank radius as afore-mentioned, since the last-mentioned inaccuracies in the positioning of the reversal points are inherently connected with the gear transmissions, i.e., with their tooth structures. In the known yarn layer driving devices of knitting machines, the adjustability of the crank radius has been intentionally omitted, especially since the working width of such machines is not subjected to any changes. For achieving at highest possible rate of revolutions for knitting machines, it is important to provide the yarn layer with such a delay at its points of reversal which will correspond to the thickness of the yarn material being processed. This means that periods of rest or delay must be provided which can be changed from case to case. This second prerequisite cannot be realized with any of the afore-mentioned devices alone or in combination.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an improved driving arrangement for a yarn layer and its carriage especially of a warp-knitting machine which not only possesses a large working width, but also a high rate of revolutions.

It is a further object of the present invention to provide an improved control of the flexible drag means such as an endless chain in a knitting machine which endless chain is coupled with a yarn layer.

In accordance with the invention, only the respective guide rollers of the chain determine the exact length of the path of movement of the layer, so that the push crank drive is designed to permit a path for the chain which is only slightly larger than the path of the yarn layer for reasons hereinafter described. Working clearances in the transmission gears will consequently no longer interfere with the length of the shuttle movement of the yarn layer.

It is a salient feature of the invention that the crank radius of the push crank drive is adjustable and permits changing of the rest periods of the yarn layer at its points of reversal without the necessity of adjusting the crank radius for the purpose of changing the path of the yarn layer. This is due not only to the fact that the length of the path of movement of the layer in knitting machines is always the same, but also to the fact that the length of the path of the layer is determined from the beginning on by the guide rollers of the chain which is coupled to the layer, and which guide rollers reroute the chain to paths which extend vertically to the path of movement of the layer.

In accordance with the invention, guide rollers are associated with each guide of the flexible drag means such as a chain driving yarn layer carriage, and the chain is rerouted by means of such guide rollers into idle-run paths lying vertically to the path of movement of the layer, and the length of the idle-run of the link which couples the layer with the chain, such idle-run being located in each instance on a path between two guide rollers, can be changed by changing the radius of the crank.

Such an arrangement provides a driving device for the yarn layer of a knitting machine which requires a push crank drive of relatively small size.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be more clearly understood from the following description of an embodiment thereof illustrated in the accompanying drawings, in which FIG. 1 is a schematic view of the entire driving arrangement of the yarn layer of a knitting machine;

FIG. 2 shows the yarn layer in larger scale at the left end of its path of movement substantially at the center of its rest position; and

FIG. 3 shows the yarn layer on the same scale as in FIG. 2, but at the right end of its path of movement and at the beginning of its rest position.

DESCRIPTION OF THE PREFERRED EMBODIMENT With reference to the drawings, it is seen that the yarn layer 1, consisting of a carriage, is put into reciprocating motion by a driving means such as an endless chain 2, the latter being driven by a shaft 3. The parts connected with the yarn laying process per se have been omitted for sake of clarity. For guiding the layer 1, it is provided with rollers 4, 5, 6 which are, in turn, guided in stationary tracks 7 and 8. The endless chain 2 runs around chain rollers 9 to 14 which are mounted stationarily, and of which chain roller 9 is the driving roller. The link which couples the layer 1 with the endlesss chain 2 consists, for example, of a bolt 15, the latter being arranged at the midpoint of center bar 16 which is displaceable transversely of the endless chain, and to which the opposite ends of two levers 17 and 18 are pivotably coupled. Levers 17 and 18 are directed oppositely with respect to each other and approximately perpendicularly to bar 16, and at their ends 50, 51, are pivotably secured to layer carriage 1. It can be seen that the coupling bolt is carried by the center bar which due to the fact that the lever ends are secured only at points 50, 51, enables the bolt 15 to follow the endless chain even if it is deflected. The chain rollers 10, 11 and 12, 13 serve for the purpose to change the direction of the endless chain 2 which is coupled with layer 1. The chain is directed into paths 19 and 20 which are vertical to the path of movement of the layer 1. If bolt 15 enters into these paths 19, 20 after the carriage 1 moved into the region of the respective roller pairs 10, 11, or 12., 13, the layer 1 comes to rest. The chain rollers 10, 11 and 12, 13 thereby determine the length of the path of movement of layer carriage 1, which length remains unchanged.

On shaft 3, which drives the endless chain 2, a small toothed gear 21 is provided in addition to chain roller 9. The small gear 21 mates with -a large toothed gear 22, which is mounted on a shaft 23, the latter being the driven shaft of a push crank drive 24. The crank of the push crank drive comprises a large toothed gear 52 which is driven by shaft 26 through a small toothed gear 25. A radial slot 27 is provided in crank 52 for the adjustable accommodation of a crankpin (not shown in the drawing). This crankpin carries a pivoted sleeve 28 for guiding a horizontal bar 29 therein. When crank 52 is rotating, bar 29 is set into up-and-down movements. Bar 29 is also provided with rollers 32, 33 which run in stationary guide means and 31. The bar 29 is also connected respectively at points 53, 54 with two endless chains 34, 35, which are respectively reversed by means of chain rollers 36, 37 and 38, 39. A third endless chain 40 is guided around chain rollers 37 and 39 and drives the driven shaft 23 by engaging chain roller 41 provided on the latter for this purpose. Crank 52 thus sets shaft 23 into alternating rotations which are transmitted, through a dual transmission, to driving shaft 3 of endless chain 2. The distance between paths 19 and 20 of endless chain 2 corresponds to the length of the path of movement of yarn layer 1, whereas the vertical distances between the respective rollers 10, 1'1 and 12, 13 determine the periods of rest of the layer 1 at the respective ends of its path of movement. These periods of standstill are variable in accordance with the radial adjustment of the crankpin of crank 52. This means that one can thus change the length of the idle run of bolt 15 which idle run takes place at each end of the path of the carriage, that is, between two guide rollers 10, 11 and 12, 13. If the radius of the crank, thereby the length of the upand-down movement of bar 29, is adjusted in such a way that the bolt 15 comes to a halt or standstill at points 42, 43 on respective shuttle runs of the layer 1, then the layer 1 has practically no rest at the end points of its movement. If, however, the bolt 15 keeps moving from points 42, 43 toward the points 44, 45 respectively, the layer 1 will have a smoothly variable rest period at the end points of its movement. It becomes obvious that longer radii of the crank drive 52 will result in longer excursions of bar 29 in guides 31, which, in turn, results in further entry of bolt 15 into the vertical paths 19, 20, leading to longer rest periods for the shuttle carriage 1 and conversely, as seen in FIGS. 2 and 3.

When bolt 15 enters into the vertical paths 19 and 20 of endless chain 2, the bar 16 is moved in vertical direction. The lower end of this movement of bar 16 is determined by a stop 46 which is provided on carriage 1. This stop 46 acts on lever 18 as shown in FIG. 1.

Although the invention has been rlescribed with respect to a specific embodiment thereof, it is not intended to limit the invention to such a specific embodiment only, but it should be interpreted in the scope of the appended claims.

What I claim is:

1. In a knitting machine such as warp-knitting machine, means for laying the yarn, guide means for supporting and guiding said yarn layer means and permitting travelling of said yarn layer means thereon back and forth across said machine flexible drag means moving in an endless path and imparting said back and forth movement to said yarn layer means, means for coupling said flexible drag means to said yarn layer means for moving said yarn layer means therewith back and forth over said guide means, first set of roller means for guiding said flexible drag :means thereover and defining a path of movement for said yarn layer means, a second set of roller means for guiding said flexible drag means thereover in a path substantially transverse to the path of movement of said yarn layer means, drive means coupled to said flexible drag means for imparting said back and forth movement thereto, said coupling means comprising a device having a configuration adapted to be carried by said flexible drag means into said transverse path, the distance of entry of said device into said transverse path defining a rest period for said yarn layer means, said drive means comprising means for variably adjusting said distance of entry into said transverse path.

2. The combination as claimed in claim 1, wherein said drive means comprises a push crank drive having an adjustable radius, the length of said radius being proportional to the distance of entry of said coupling means into said transverse path, said device comprises lever means.

3. The combination as claimed in claim 2, wherein said yarn layer means comprises a carriage including guide rollers for travelling said carriage along said guide means, said device comprising a center member carrying a coupling bolt engaged by said flexible drag means, said lever means comprising a pair of oppositely directed lever arms pivotably connected to each end of said center member and pivotably secured to said carriage, whereby said coupling bolt is adaq'atedto follow said flexible drag means into said vertical path when said radius is so adjusted.

4. The combination as claimed in claim 3, wherein said flexible drag means is an endless chain.

5. The combination as claimed in claim 3, further comprising stop means for limiting the movement of said center member during movement of said carriage over said path thereof. 1

References Cited UNITED S'IjATES PATENTS 1,812,700 6/1931 Johnson 66-84 1,837,101 12/1931 Berner 66-64 1,902,151

3/1933 Welch et a1. 6660 Cobert 66-126 FOREIGN PATENTS France. Germany. Great Britain. Great Britain. Great Britain. Great Britain.

U.S. Cl. X.-R. 

